1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
# Miro - an RSS based video player application
# Copyright (C) 2005-2008 Participatory Culture Foundation
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#
# In addition, as a special exception, the copyright holders give
# permission to link the code of portions of this program with the OpenSSL
# library.
#
# You must obey the GNU General Public License in all respects for all of
# the code used other than OpenSSL. If you modify file(s) with this
# exception, you may extend this exception to your version of the file(s),
# but you are not obligated to do so. If you do not wish to do so, delete
# this exception statement from your version. If you delete this exception
# statement from all source files in the program, then also delete it here.
from itertools import count
from miro import database
def makeSimpleGetSet(attributeName, changeNeedsSave=True):
"""Creates a simple DDBObject getter and setter for an attribute.
This exists because for many DDBOBject attributes we have methods like the
following:
def getFoo(self):
self.confirmDBThread()
return self.foo
def setFoo(self, newFoo):
self.confirmDBThread()
self.foo = newFoo
self.signalChange()
"""
def getter(self):
self.confirmDBThread()
return getattr(self, attributeName)
def setter(self, newValue):
self.confirmDBThread()
setattr(self, attributeName, newValue)
self.signalChange(needsSave=changeNeedsSave)
return getter, setter
class TrackedIDList(object):
"""Creates a view that tracks a list of DDBObject IDs.
The view will have the corresponding DDBObject for each ID in the list and
will be in the same order.
Attributes:
view -- Database view that tracks the list of ids
"""
def __init__(self, db, idList, sortFunc=None):
"""Construct an TrackedIDList.
This object will keep a reference to idList. When insertID, appendID,
removeID, or moveID are called idList will be modified to
reflect the change.
"""
if sortFunc == None:
sortFunc = self.sort
self.trackedIDs = set()
self.positions = {}
self.list = idList
self.db = db
pos = count()
for id in idList:
self.positions[id] = pos.next()
self.trackedIDs.add(id)
self.extraFilterFunc = lambda x: True
self.filter1 = db.filter(self.filter)
self.filter2 = self.filter1.filter(self.extraFilter)
self.view = self.filter2.sort(sortFunc, resort=True)
def recomputeSort(self):
self.filter2.recomputeSort(self.view)
def sort(self, a, b):
return self.positions[a[1].getID()] < self.positions[b[1].getID()]
def filter(self, object):
return object.getID() in self.trackedIDs
def extraFilter(self, object):
return self.extraFilterFunc(object)
def setFilter(self, extraFilterFunc):
self.extraFilterFunc = extraFilterFunc
self.filter1.recomputeFilter(self.filter2)
def _sendSignalChange(self, id):
if self.db.idExists(id):
self.db.getObjectByID(id).signalChange(needsSave=False)
def __contains__(self, id):
return id in self.trackedIDs
def getPosition(self, id):
"""Get the position of an id in the list. If id is not in the list a
KeyError will be raised."""
return self.positions[id]
def appendID(self, id, sendSignalChange=True):
if id in self:
raise ValueError("%s is already being tracked" % id)
self.positions[id] = len(self.list)
self.trackedIDs.add(id)
self.list.append(id)
if sendSignalChange:
self._sendSignalChange(id)
def insertID(self, pos, id):
if id in self:
raise ValueError("%s is already being tracked" % id)
for toMove, oldPos in self.positions.items():
if oldPos >= pos:
self.positions[toMove] += 1
self.positions[id] = pos
self.list.insert(pos, id)
self.trackedIDs.add(id)
self._sendSignalChange(id)
def removeID(self, id):
removedPos = self.positions.pop(id)
for toMove, oldPos in self.positions.items():
if oldPos > removedPos:
self.positions[toMove] -= 1
del self.list[removedPos]
self.trackedIDs.remove(id)
self._sendSignalChange(id)
def moveID(self, id, pos):
"""Move an id from it's current position to a new position, shifting
the rest of the list to accomidate it.
"""
currentPos = self.positions[id]
if currentPos > pos:
minChange = pos
maxChange = currentPos-1
delta = 1
else:
minChange = currentPos+1
maxChange = pos
delta = -1
for toMove, oldPos in self.positions.items():
if minChange <= oldPos <= maxChange:
self.positions[toMove] = oldPos + delta
self.positions[id] = pos
del self.list[currentPos]
self.list.insert(pos, id)
self._sendSignalChange(id)
def moveIDList(self, idList, anchorID):
"""Move a set of IDs to be above anchorID.
More precicely, we move idList so it is one contiguous block, in
between anchorID and the first id not in idList. The ids in idList
won't change position relative to each other.
If anchorID is None, idList will be positioned at the bottom.
"""
if anchorID in idList:
return
toMove = [(self.getPosition(id), id) for id in idList]
toMove.sort()
for oldPos, id in toMove:
self.removeID(id)
for oldPos, id in toMove:
if anchorID is not None:
anchorPos = self.getPosition(anchorID)
self.insertID(anchorPos, id)
else:
self.appendID(id)
|
